Look for one who is fiercely loyal to you. But you must never betray that loyalty.
Look for someone that will accept and allow you to be the leader in the house.
Look for someone that naturally and normally speaks with politeness, a low tone of voice, able to control her emotions and feminine. Any signs of masculine traits, dump her.
Looks will fade, and very badly after 50. Even the most beautiful wife, after 2 years of marrying her, you won't see her as beautiful anymore.
Character and personality lasts forever.